KNOXVILLE, Tenn. -- The defoliant Agent Orange, which contains dioxin, was sprayed on thousands of acres of brush in the Tennessee Valley for 15 years before scientists discovered the herbicide was dangerous, agency officials said.
'It's time that people know,' TVA ecologist Dennis McCarthy said Wednesday.
McCarthy also revealed, under questioning by a reporter, that the TVA tested the suspected cancer-causing defoliant Agent Orange twice on 44 remote acres in Tennessee as an experiment for the Army.
The herbicide that was used by TVA for 15 years is called 2,4,5-T. It is an ingredient in Agent Orange. Both substances contain dioxin.
McCarthy said soil samples taken from areas where the herbicides were sprayed in the 1950s and 1960s found no detectable levels of dioxin, which was found in such large quantities in Times Beach, Mo., that the government bought the town and ordered everyone to leave.
'I don't think there's any dioxin left, but I can't say there's none out there. I don't think anybody's in danger. If there are any dioxins left out there, they are in low enough levels where they are not a problem and probably never were,' McCarthy said.
Agent Orange was sprayed in Monroe County in east Tennessee and in Hickman County southwest of Knoxville in 1964 and 1968. Agent Orange was used to kill underbrush during the Vietnam War and its use has been banned by the Environmental Protection Agency.
The herbicide 2,4,5-T was used on thousands of acres to kill brush wherever TVA had transmission lines in seven Southeastern states. The use of 2,4,5-T has been severely restricted by the EPA.
In the late 1960s when the toxicity of dioxins was learned, TVA began clearing 95 percent of its brush mechanically and using a chemical called Tordon, known as Agent White, for the rest.
TVA spokesman Dick Green said officials had not revealed the testing of Agent Orange before because no one asked about it.
'We did not continue to use it ourselves. We were using other products,' Green said.